Doing your ab exercises on an incline bench makes them more challenging because they force you to lift more of your body weight. Adding a medicine ball into the mix increases the load even further, so only those who have significantly built up their abs should incorporate incline-bench ab exercises into their workouts. Once you're ready for a new ab challenge, there are specific ab exercises you can do with an incline bench and medicine ball.
Get into position for the medicine ball sit-up by hooking your feet under the foot brace at the top of the incline bench so that you're lying on your back with your head positioned below your feet. Hold the medicine ball against your chest with both hands. Raise your torso up from the bench by bending at the waist and come up to a seated position. Control your body back down to the bench until the back of your shoulders make contact with the bench and then go right into the next repetition. These types of sit-ups primarily develop the rectus abdominus, which is the major muscle in your abs, but also recruit your obliques and hip flexors.
The medicine-ball twist exercise places greater emphasis on the obliques -- the muscles along the sides of your abs -- while also forcing your rectus abdominus to work isometrically. Your abs working isometrically means that they are forced to hold you in a set position. The medicine-ball twist and medicine ball sit-ups share the same starting position. With a medicine ball at your chest, raise your torso up from the bench until you travel halfway up to the top. Hold this angle at your waist as you twist your torso to the left so that your shoulders are facing to the side and then twist back to the right. Continue twisting back and forth until your muscles start to get too tired and then lower your torso back to the bench.
Leg and Hip Raise
The leg and hip raise exercise begins with you flipped around so that you're on your back but holding the feet hooks at the top of the incline bench with your hands and your legs are positioned below your head. Squeeze a medicine ball between your knees or feet. This is your starting position. Raise your legs by bending your knees and bringing them up to your torso. Keep lifting until you raise your hips up off the bench. Lower your hips back down and then extend your legs to return to starting position. The leg and hip raise is similar to medicine ball sit-ups in that it primarily develops your rectus abdominus, but also requires help from your obliques and hip flexors.
During the medicine-ball sit-up exercise, it's your abs that begin the movement as you curl your spine, but then your hip flexors come in to help you bend your hips so that you can raise up to the sitting position. When your hip flexors contract, they pull on your spine. It is important, therefore, that you engage your abdominals to counteract that stress. Otherwise, your lower back can hyperextend and you can suffer from back pain. This is why it's important not to add the medicine-ball sit-up exercise into your workout until you have an abdominal-strength base.